German patent document DE 101 48 218 A1 discusses a method for operating a fuel injection system using a quantity control valve. The known quantity control valve is implemented as a solenoid valve which is operated electromagnetically by a solenoid and has a magnetic armature and corresponding path-limiting stops. The known solenoid valve is open in the energized state of the coil. However, such quantity control valves, which are closed in the currentless state of the solenoid, are also known from the market. In the latter case, the solenoid is triggered using a constant voltage or a clocked voltage (pulse width modulation, “PWM”) to close the quantity control valve so that the current in the solenoid increases in a characteristic manner. After switching off the voltage the current drops again in a characteristic manner, so that the quantity control valve opens.